Clock



FIG. 1 is a perspective view of a clock showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof; and,

FIG. 4 is a left side elevational view thereof, the right side view being a mirror image thereof.

The bottom of the clock is flat and unornamented.

The broken line showing of "buttons" in all figures is for environmental purposes only and forms no part of the claimed design. 

The ornamental design for a clock, as shown and described. 